Investigating the Use of Coastal Blue Imagery for Bathymetric Mapping of Inland Water Bodies

Abstract

<p><strong>Abstract.</strong> In this contribution, we report on an experimental airborne data acquisition with two medium format cameras (Coastal Blue, RGB) and a topo-bathymetric laser scanner for capturing the bathymetry of a dozen of groundwater supplied lakes located near Augsburg, Germany. The specific research question was to investigate whether the use of high-resolution Coastal Blue imagery (λ<span class="thinspace"></span>=<span class="thinspace"></span>400–460<span class="thinspace"></span>nm) provides added value for mapping bathymetry and characterization of water bottom features. While data processing is still in progress, preliminary results indicate that the blue (λ<span class="thinspace"></span>=<span class="thinspace"></span>420–500<span class="thinspace"></span>nm) and green (λ<span class="thinspace"></span>=<span class="thinspace"></span>490–570<span class="thinspace"></span>nm) color channels of the RGB camera are better suited for estimating bathymetry, but the Coastal Blue channel adds an additional water penetrating band increasing the number of useful band combinations with a positive effect on the water bottom classification capabilities. Whereas Coastal Blue channels are rather used from satellite platforms (Landsat 8, WorldView-2) with spatial resolutions in the meter range, our experiment aims at using higher resolution Coastal Blue imagery with a ground sampling distance of around 5<span class="thinspace"></span>cm enabling not only spectrally based shallow water depth mapping but also the application of multi-media photogrammetry in high spatial resolution. To the best of our knowledge the use of high-resolution Coastal Blue captured from airborne platforms is novel in the context of mapping shallow water bathymetry.</p>

BathyNet: A Deep Neural Network for Water Depth Mapping from Multispectral Aerial Images

“…Both cameras were equipped with a 50 mm wide-angle lens. A more detailed description of the camera system including the transmission curves of the individual spectral channels is provided in Mandlburger et al (2018).…”

Comparison of Subaquatic Digital Elevation Models From Airborne Laser Scanning and Imagery

“…The airplane was equipped with a topo-bathymetrical laser scanner (Riegl VQ-880-G) together with two 100 Mpix cameras (IGI DigiCAM 100). One was a standard RGB-camera, while the second one was operated in a monochromatic mode together with a Coastal-Blue filter (λ=400-460 nm) (Mandlburger et al, 2018). Altogether four stripes were acquired at flight speed of 100 knots (50 m/s).…”

“…As mentioned before, the used camera was a IGI DigiCAM 100 medium format camera with a resolution of 10608x8708 Pixel (100 Mpx) together with a 50 mm lens. The camera itself was developed from a PhaseOne iXU-RS 1000 (Mandlburger et al, 2018). For the tests, the RGB images were processed exclusively in favour of the Coastal-Blue data, because of the more suitable characteristics for automatic image analysis (Mandlburger et al, 2018).…”

“…The camera itself was developed from a PhaseOne iXU-RS 1000 (Mandlburger et al, 2018). For the tests, the RGB images were processed exclusively in favour of the Coastal-Blue data, because of the more suitable characteristics for automatic image analysis (Mandlburger et al, 2018). For geo-referencing GNSS and INS data were acquired during the flight.…”

Improvement of Full Waveform Airborne Laser Bathymetry Data Processing based on Waves of Neighborhood Points

“…Thus, increasing attention has been paid to the development of rapid methods of object detection and monitoring of possible obstacles found in a sea transport pathway. Thus far, sonar measurements have been used for this purpose [1], but also other remote sensing methods can be a data source for bathymetric measurements such as: stereophotogrammetry of underwater images [2] and image matching of photogrammetric images [3][4][5]. Nevertheless, special attention should be given to methods using airborne laser bathymetry, because this measurement method can be used as a supplement or a complete alternative to sonar data [6].…”